Marcel wave
Deep, regular waves made with heated tongs, invented by the Paris hairdresser Marcel Grateau in 1872.
Also: marcelling
The marcel wave is a pattern of deep, even waves set with heated curling tongs. The method was developed by the French hairdresser Marcel Grateau in Paris in 1872, using tongs heated on a stove and turned to make a wave rather than a curl. Marcelling, as it was called, was the fashion for decades and paired well with the short bobs of the 1920s. Finger waving gave a similar look without heat.